Conventional skateboards utilize pivoting truck assemblies attached to a solid wood riding deck. These truck assemblies typically include a shaft, cups, elastomeric bushings, washers, mounting plates, a single axle, bearings, two elastomeric wheels and fasteners. The skateboard rider steers the skateboard by leaning and applying pressure to opposite lateral sides of the skateboard deck, which in turn causes the truck assembly to pivot and rotate the single truck axle about a single axis perpendicular to the skateboard deck.
Conventional truck assemblies provide a fairly rugged and reliable assembly, but suffer from a number of disadvantages including: a) the turning ability of existing skateboards is very limited due to existing truck designs and b) existing skateboards have no provision to adjust steering response to the amount of angle and pressure the rider applies to the deck. Existing truck assemblies typically include two wheels attached to a single axle. This arrangement allows only small axle rotation resulting in very limited skateboard turning capability. To execute tight turns, the rider must perform the awkward maneuvers of forcing the back end of the skateboard down which lifts the forward truck assembly off the surface on which it is riding and rotating the skateboard about the rear truck assembly. Less experienced skateboard riders must sometimes stop the skateboard, lift the skateboard off the ground and reposition it in its new direction. This is especially true around very tight turns. While some improvement in skateboard turning capability is possible by changing the truck's elastomeric bushing material and shaft tightness, this improvement typically has the undesirable effect of causing skateboard wobble, wheel “bite” (the wheel hits the deck causing the skateboard to stop rapidly) and instability. Additionally, for every degree of deck rotation the rider applies, a fixed amount of turning radius results. If for instance a rider wants very large changes in steering radii with relatively small changes in initial deck rotation and then smaller changes in steering as more deck rotation is applied, existing skateboards cannot satisfy this need. Existing skateboards provide only a fixed, linear steering output in relation to skateboard rider input.
To overcome the disadvantages of conventional truck assemblies, it is desirable to provide a truck assembly that permits very tight, small turning radius capability without the need to lift the forward truck assembly or the entire skateboard from the surface on which it is riding. Such a truck assembly may maintain stability and eliminate wobble and wheel bite for all truck settings and adjustments. It is also desirable to provide a truck assembly that permits variable and adjustable steering response. Such adjustability may be utilized, for example, to allow small deck rotations to provide large changes in skateboard steering radii or vice verse, i.e., to allow large deck rotations to make small changes in steering radii.